[RFC PATCH v2 3/4] arm64:thunder: Add initial dts for Cavium's Thunder SoC in 2 Node topology.

Arnd Bergmann
2014-11-24T17:01:58Z

On Monday 24 November 2014 11:32:46 Roy Franz wrote:
> >
> > I don't know how much history is behind this binding. Have you looked
> > at the sPAPR way of doing this? I don't remember exactly how that is
> > done, but we'd need a good reason to discard that and implement
> > something else for arm64.
> >
> > If we create a new binding, I don't think the 'numa-map' node you
> > have here is the best solution. We already have device nodes for each
> > memory segment and each CPU in the system. Why not work with those
> > nodes directly?
>
> The DT memory nodes don't exist in an EFI system, as the EFI memory
> map is used instead.
> Using EFI as the boot firmware doesn't require the use of ACPI for
> hardware description,
> so the EFI/DT case is one that we should support.

But they /could/ exist, right? Can we just require them to be
present in order to use NUMA features?

I don't think it's a good idea to require a new representation
of the memory nodes in DT to make NUMA work when we already have
one that is almost always there.

Arnd